Li Kebin, Wei Hongshuang, Shu Changlong, Zhang Shuai, Cao Yazhong, Luo Chen, Yin Jiao
State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China.
Institute of Plant and Environment Protection, Beijing Academy of Agricultural and Forestry Sciences, Beijing 100097, China.
Comp Biochem Physiol Part D Genomics Proteomics. 2017 Dec;24:1-11. doi: 10.1016/j.cbd.2017.07.001. Epub 2017 Jul 24.
A sophisticated olfactory system is part of the explanation for the prominence of insects among animals because of the essential roles of the olfactory system in foraging, host seeking, mating, ovipositing and avoiding toxic substances. In this study, we sequenced and analysed the transcriptomes of olfactory tissue (antennae) and non-olfactory tissue (legs) of the scarab beetle, Holotrichia oblita Faldermann, which is a serious underground pest in China. We obtained approximately 80.2 million 150bp reads that were assembled into 61,038 unigenes with an average length of 890bp. Among the transcripts, 70% of the unigenes were annotated. A total of 44 odorant receptors (ORs) and 9 ionotropic receptors (IRs) were identified based on homology searches. Then, quantitative real-time PCR experiments were performed to investigate the expression patterns of 32 putative chemosensory genes. The results showed that these genes were highly expressed in olfactory organs (antennae) and might play a key role in the olfaction-related behaviours in H. oblita. Based on the results of our phylogenetic analysis and the detailed tissue and sex-biased expression characteristics, the different roles of the receptor proteins in the olfactory system were also indicated. The results of this study will provide the foundation for further understanding of the olfactory odorant receptors of H. oblita at the molecular level and ultimately help to develop novel targets for manipulating this pest.
复杂的嗅觉系统是昆虫在动物界中占据突出地位的部分原因，这是因为嗅觉系统在觅食、寻找宿主、交配、产卵以及避免接触有毒物质等方面发挥着至关重要的作用。在本研究中，我们对中国一种严重的地下害虫——华北大黑鳃金龟（Holotrichia oblita Faldermann）的嗅觉组织（触角）和非嗅觉组织（腿部）的转录组进行了测序和分析。我们获得了约8020万个150bp的 reads，这些 reads 被组装成61038个单基因，平均长度为890bp。在这些转录本中，70%的单基因得到了注释。基于同源性搜索，共鉴定出44个气味受体（ORs）和9个离子型受体（IRs）。随后，进行了定量实时PCR实验，以研究32个假定的化学感应基因的表达模式。结果表明，这些基因在嗅觉器官（触角）中高度表达，可能在华北大黑鳃金龟与嗅觉相关的行为中发挥关键作用。基于我们的系统发育分析结果以及详细的组织和性别偏向表达特征，还揭示了受体蛋白在嗅觉系统中的不同作用。本研究结果将为在分子水平上进一步了解华北大黑鳃金龟的嗅觉气味受体奠定基础，并最终有助于开发针对这种害虫的新型防治靶点。
